Dental-engine hand-piece



(No Model.)

G.. M. RICHMOND. DENTAL ENGINE HAND PIECE.

No. 434,952. Patented Aug. 26, 1890.

INVENTOR l wc mums vsrzns ce., PHD-royaume., wAsuwc-ron. u. c.

UNITED STATES PATENT OFFICE.

CASSIUS M. RICHMOND, OF NEV YORK, N. Y., ASSIGNOR TO THE S. S.

WHITE DENTAL MANUFACTURING COMPANY, OF PHILADELPHIA,.

PENNSYLVANIA.

DENTAL-ENGINE HAN D-PIYECE.

SPECIFICATION forming part of Letters Patent No. 434,952,11ated August 26, 1.890.

Application tiled June 2, 1890. Serial No. 353,932. (No model.)

To all whom it may concern,.-

Be it known that I, CAssIUs M. RICHMOND;

of the city, county, and State of .New York, have invented certain new and useful Improvements in Dental-Engine Hand-Pieces, of which the following is a specification.

My invention relates to certain improvements, as hereinafter claimed, in that class of dental-engine hand-piecesgfor drills and burring-tools in which the shanks of the tools are connected with the hand-pieces by way of toolclamping and actuating spindles made each in two parts with the one part having endwise movement in the other, for engaging and locking the tool-Shanks in place.

My object is to provide simple, strong, inexpensive, and readily-operated means for irmly securing the tools to their spindle.

In the accompanying drawings, Figure 1 is a longitudinal view of a hand-piece with my improvements applied thereto; Fig. 2, aview of the same, on an enlarged scale, showing most of the parts in central longitudinal section. Fig. 3 is a longitudinal View of the sectional or two-part tool-actuating spindle detached. Figs. 4 and 5 are similar views of the spindle-sections separated from each other.

Fig. G is a section ona considerably-enlarged scale on the line 6 of Fig. 3.

Within a hand-piece A, composed of casin gsections connected in a suitable well-known way, is mounted to rotate in proper bearings,

between the slide and spindle-section is made, as shown, in the following way: A collar E, secured to the spindle-section, is provided with an annular groove CZ, into which project the ends of two pins e, screw-attached to the A groove f is provided within the slide.

tubular spindle-section B, extending from the outer end of this section inward for aportion of the length thereof. This groove is formed by securing in the tubular spindle-section a bushing of suitable dimensions cut away or having an opening along one side to constitute the groove f when the bushing isin place.

The inner spindle-section C has a locking pin or key G at its outer end adapted for engagement with the internal groove f of the tubular casing-section. This key is partially wedge-shaped, being slightly tapered on its outer surface from its free end inward for a portion of its length. The locking-key is by preference provided on its inner surface with a V-shaped groove extending from its outer end inward .for a portion of "its length, or it may be its Whole length.

The shank II of the tool shown is of wellknown forni, being round and provided with the reduced inner end, forming a flattened portion to rest upon a shoulder hof the tubular spindle-section. Itis not, however, necessary to provide the shoulder 7i and reduced flattened end'of the tool-shank.

In the operat-ion of securing a tool in place, the inner section C of the spindle having been retracted, the tool-shank is inserted into the tubular spindle-section, and the inner spindlesection then moved outward with suiiicient force to firmly clamp the tool-shank between the locking-key and the inner' surface of the tubular spindle-section opposite the key. A very rm frictional grip is exert-ed upon the tool-sh ank which can quickly be disconnected from the hand-piece by moving the sliding spindle-section inwardly.

I claim as my inventionl. The tool-clamping spindle consisting of the outer tubular section provided with the internal groove extending longitudinally thereof, and the endwise-movable innerI section provided with the taperedV locking-key engaging with the groove of the tubular section, substantially as and for the purpose set forth.

2. The combination of the hand-piece, the two-part tool clamping and actuating spindle consisting of the outer tubular section pro- In testimony whereof I havehereunto subscribed my'name.

CASSIUS M. RICHMOND. Witnesses:

A. P. W. KINNAN', WMJ. MCCLELLAND. 

